Benjamin j



(No Model.) 7

. B. J. PORSTER.

ATMOSPHERIC AIR MOTOR.

No. 274,305. Patented Mar.20,1883.

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' Toall whom it may concern:

' UNTTED STATES PATENT @FFICE.

BENJAMIN J. FORSTER, OF GLEN WILLIAM, ONTARIO, CANADA.

ATMOSPHERIC- Al R MOTORQ SPECIFICATION forming-part of Letters Patent 0. 274,305, dated March 20, 188B, Application filed November 4, 1882. (No model.)

Be it known that I, BENJAMIN JAMES Foxs TER, a subject of the Queen of Great Britain, residing at the village of Glen William, in the county otHalton, in the Province of Ontario,Dominion of Canada, have invented a certain new and useful Improvement in Atmospheric-Air Motors, of which the following is a specification.

This invention relates to certain improvements in that class of air-motors in which the expansion and contraction of airin a flexible receptacle are utilized as a motive power, which is stored up for use as desired; and the invention consists in the special construction and arran gement of parts hereinafter fully set forth.

Figure l is an elevation exhibiting an arrangement of mechanism for producing the desired result. Fig. 2 is an enlarged detail of dogs and endless chain. Fig. 3 is adetail of spring-connection. i

It is a well-established fact in pneumatics that air will expand three-eighths of its bulk between a freezingtemperature and the boiling-pointof water-in other words, that eight measures of air at the freezing-temperature be- 7 come eleven at the boiling-point of water. It

is also well establised in pneumatics that air vpreserves an equable rate of expansion at all temperatures. Its increase of bulk, for ex ample, being the same from zero to 100--as from 100 to 200, and as its expansion from 32 to 212 Fahrenheit amounts to three eighths of its bulk at 32-it follows that every degree on this scale corresponds to a change in its bulk amounting to one four-hundred-andeighthieth of the bulk at 32. I have mentioned this maxim in pneumatics in order that the principle of my mechanism may be understood and its operation appreciated as produced by changes in the temperature of the atmosphere. If a hermetically-sealed vessel containing nothing but air be subjected to heat,

the expansion of the air within it produces a power increased in proportion to the heat applied,and, under certain circumstances,in proportion to the volume of the air contained within the vessel. .It is with a view of utilizing the power produced by the law of pneumatics referred to that the apparatus which I will now proceed to describe has been devised.

A represents a flexible cylinder, preferably subjected to a greater external pressure than that produced within it. If this hermeticallysealed cylinder A is collapsed, but at the same time contains a certain volume of air, it follows that, owingto the construction of the cylinder, as explained, should heat be applied to it, the expansion of the air within it will force its two heads apart, which heads will again come together when the air within the cylinder has cooled down to its original temperature. With the view of utilizing this expansion and contraction I provide the following simple mechanism: The lower head, B, of the cylinder A is fixed to a table, 0. The other end, B, is provided with suitable friction-rollers,D, held opposite to each other on the said head and brought in contact with the vertical guide-bars E. The cylinderA is in this manner held in a vertical position, while its free movement, caused by the expansion and contraction of the air within it, will not be injurionsly aifected by the means explained for guiding its movement in a given direction.

F are two rods connecting the top B with the cross-head G, provided with friction-rollers H, which rollers, like the friction-rollers D, fit and work on the vertical guides E. It will thus be seen that the movement of the head B, produced by the expansion or contraction of the air within the "essel A, will impart a similar movement to the cross-head G.

With the View of balancing the weight of the head B and cross-head G, I provide counterbalance-weights, I, which are connected to the cross-head G by the chains J, passingover pulleys K, which are held in suitable brackets supported in the frame-work of the machine. By thus providing balance-weights the force produced by the expansion of the air will have exactly the same effect on the mechanism as an equal force produced by the contraction of the air within the cylinder A.

L is an endless chain passing round the pul leys M and N, held in suitable brackets secured to the frame-work of the machine, as illustrated. The chain L passes through holes in the cross-head G, which cross-head has pivoted upon it, in proximity to the chain L, two dogs, 0 and P, the dog 0 being set against the chainL so that it will engage therewith only when the cross-head Grascends, while the dog I? is set so as to engage with the same chain, but on the opposite side of the pulley, when the cross-head descends. By this arrangement of dogs it will be seen that the pulleys Mand N will always revolve in the same direction, whether the cross-head moves up or down in its guides, as explained. As the volume of air within the vessel or cylinder A would not in itself be sufficient to produce a power applicable for practicable purposes, I provide an additional vessel, Q, which is also hermetically sealed, but is suitably connected by a pipe, It, or otherwise to the vessel A,'in order to constitute an air-reservoir for the supply of pressure to the said flexible vessel A.

The number and size of the reservoirs Q can of course be indefinitely increased; but for the purpose of explaining my invention it will be sufficient to show one reservoir only.

If the apparatus constructed as described is placed in a position where it will be affected by the differences in the temperature of the atmosphere, which varies in summer in this latitude as many as between noon and midnight, it follows that the expansion and contraction of the air thus produced within the chamber A, re-enforced by the expansion and contraction of the air within the reservoir Q, will produce, as herein explained, a reciprocating movement to the cross head G, which movement is imparted by the dogs 0 and P to the chain L and through it to the spindles on the pulleys M and N. It follows that if these spindles or either one of them is suitably connected to a motor propelled by a spring or its equivalent for storing power and reproducing the same, the said spring or its equivalent will be constantly supplied with fresh power by the reciprocating movement of the flexible vessel A, and thus so long as the apparatus is subjected to atmospheric changes so long will power be supplied to the motor, which reproduces the samein the usual manner.

Although the greatest motion will be produced when the temperature changes to the greatest extent, it will of. course be understood that upon every slight change in the temperature the motor will be affected to a certain extent. If exposed to the bright rays of the sun, the air will expand. Should the sun become clouded for a short period, the air will naturally contract, and so on during the whole irregular, sometimes fast and sometimes slow,

and sometimes imparting no movement at all, it is important that the mechanism devised to store the power produced by the motion of my apparatus should be so constructed thatthe irregular manner in which the power is applied to it should have no effect on its working.

In Fig. 3 I exhibit a plan by which a spring may be wound up without affecting the motor propelled by the said spring. In this figure the spring S is attached at one end to the spindle M, its other end being connected to the flange T, to which flange the main cogwheel U is connected. The spindle is therefore entirelyindependent of the main driving cog-wheel U, except so far as it is connected by the spring. When thespindle is revolving the spring is wound up; but in so winding it it does not affect the movement of the main drivin g cog-wheel U. Consequently the spindle M may be caused to revolve quickly or slowly, according to the movement of my apparatus, without affecting in any way the movement of the main driving cog-wheel, except so far as re-enforcin g the power to be applied to it.

In constructing my apparatus its size willv of course be regulated to suit the particular work it is intended to perform. The extreme apparatus of any unlooked-for strain.

In Fig. 1, V is a cup of mercury communiwhat is. termed a safety-valve, to relieve the V eating with the interior of the reservoir Q. W e

is a pipe leading from the reservoir Q andfitting into the mercury in the cup V, the interior diameter of 'the cup being greater than the outer diameter of the pipe.

In the event of the expansion within the reservoir Q being greater than required to impart the desired movement to the cylinder A, instead of exerting the extra strain on the said cylinder, the surplus power produced by this extra expansion is relieved by the escape of air through the pipe W, and thence through the seal of mercury out into the atmosphere.

It will of course be understood that the seal of mercury is of such a size as will simply balance the extreme pressure which the cylinder "A is calculated to withstand.

In the event of the contraction of the air.

the expansion and contraction of the air within it, due to theincrease or decrease in the'temperature of the atmosphere, shall impart movebination with mechanism so arranged in con- 'nection with the flexible vessel that the reciprocating movement of thefvessel' produced by ment to a motor capable of storing the power thereby produced and reproducing the same at such timesas required, substantially as andlfor the purpose specified.

2; In an apparatus to'produce motion by the expansion and contraction of air, due to theincrease or decrease in the temperature of the atmosphere, an air-tight flexible vessel having a rigid topframe moving in guides, the gravity of, which is counterbalanced by a weight or weights connected to mechanism deriving its motion from the expansion and contraction of the said vessel, in combination with an inflexible air-reservoir, also air-tight, but communicating with the flexible vessel, substantially as and for'the purpose specified;

3. In an apparatus for utilizing the changes in the temperature of the atmosphere, and in which motor-power is applied to mechanism by the reciprocating movement of an air-tight flexible vessel, the combination of an inflexible air-tight vessel connected to the flexible vessel and provided with a mercurial safety-valve, substantially as and for the purpose specified.

at. An air-tight flexible cylinder A, fixed at one end to the table G, and having its movable head provided with friction-rollers D, working in guide'bars E, in combination with the counterbalance-weights I, substantially as and for the purpose specified.

5. In an apparatus for utilizing the changes in the temperature of the atmosphere by the expansion and contraction of a flexible cylinder, an endless chain, L, passing around the pulleys M and N, in combination with the cross-head G, connected to and affected. by the movement of the flexible cylinder, and having pivoted on it the dogs 0 and P, arranged to engage with the chain L, substantially as and for the purpose specified.

6. In an apparatus for utilizing the changes in the temperature of the atmosphere by the expansion and contraction of a flexibleicylininder arranged to impart a rotary movement to a spindle, the combination of aribbon-sprin g, S, the inner end of which is connected. to the spindle M and the outer end to the flange T, substantially as and for the purpose specified.

B. J. FORSTER.

Witnesses Units. 0. BALDWIN, LEWIS TOMLINSON. 

